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8ceafbfa91
Pull DMA mask updates from Russell King:
"This series cleans up the handling of DMA masks in a lot of drivers,
fixing some bugs as we go.
Some of the more serious errors include:
- drivers which only set their coherent DMA mask if the attempt to
set the streaming mask fails.
- drivers which test for a NULL dma mask pointer, and then set the
dma mask pointer to a location in their module .data section -
which will cause problems if the module is reloaded.
To counter these, I have introduced two helper functions:
- dma_set_mask_and_coherent() takes care of setting both the
streaming and coherent masks at the same time, with the correct
error handling as specified by the API.
- dma_coerce_mask_and_coherent() which resolves the problem of
drivers forcefully setting DMA masks. This is more a marker for
future work to further clean these locations up - the code which
creates the devices really should be initialising these, but to fix
that in one go along with this change could potentially be very
disruptive.
The last thing this series does is prise away some of Linux's addition
to "DMA addresses are physical addresses and RAM always starts at
zero". We have ARM LPAE systems where all system memory is above 4GB
physical, hence having DMA masks interpreted by (eg) the block layers
as describing physical addresses in the range 0..DMAMASK fails on
these platforms. Santosh Shilimkar addresses this in this series; the
patches were copied to the appropriate people multiple times but were
ignored.
Fixing this also gets rid of some ARM weirdness in the setup of the
max*pfn variables, and brings ARM into line with every other Linux
architecture as far as those go"
* 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm: (52 commits)
ARM: 7805/1: mm: change max*pfn to include the physical offset of memory
ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations
ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations
ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function
ARM: 7794/1: block: Rename parameter dma_mask to max_addr for blk_queue_bounce_limit()
ARM: DMA-API: better handing of DMA masks for coherent allocations
ARM: 7857/1: dma: imx-sdma: setup dma mask
DMA-API: firmware/google/gsmi.c: avoid direct access to DMA masks
DMA-API: dcdbas: update DMA mask handing
DMA-API: dma: edma.c: no need to explicitly initialize DMA masks
DMA-API: usb: musb: use platform_device_register_full() to avoid directly messing with dma masks
DMA-API: crypto: remove last references to 'static struct device *dev'
DMA-API: crypto: fix ixp4xx crypto platform device support
DMA-API: others: use dma_set_coherent_mask()
DMA-API: staging: use dma_set_coherent_mask()
DMA-API: usb: use new dma_coerce_mask_and_coherent()
DMA-API: usb: use dma_set_coherent_mask()
DMA-API: parport: parport_pc.c: use dma_coerce_mask_and_coherent()
DMA-API: net: octeon: use dma_coerce_mask_and_coherent()
DMA-API: net: nxp/lpc_eth: use dma_coerce_mask_and_coherent()
...
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html